Clinical characteristics of study subjects
| COPD | Healthy controls | |
| M/F | 14/4 | 8/3 |
| Mean (SD) age (years) | 62 (8) | 58 (8) |
| Mean (SD) pack years smoking | 28 (22) | 25 (15) |
| Mean (SD) years since quitting smoking | 11 (12) | 15 (10) |
| Never smoker (n) | 3 | 0 |
| Chronic bronchitis (n) | 14 | 0 |
| Mean (SD) FEV1 (% predicted) | 59 (13)1-150 | 104 (11) |
| Mean (SD) ΔFEV1 (% predicted) | 6 (2) | 3 (3) |
| Sputum induction (n) | 18 | 11 |
| Bronchoalveolar lavage (n) | 16 | 11 |
| Bronchial biopsy (n) | 17 | 10 |
↵1-150 p<0.001, COPD versus healthy controls.
ΔFEV1 after inhalation of 1 mg terbutaline.